Jail door and operating mechanism



Aug. 11, 1936.

J. L. W|LLlAMS JAIL DOOR AND OPERATING MECHANISM Filed April 5, 1934 2 Sheets-Sheet l l'mventor 1,

Aug. 11, 1936. w s 2,050,987

JAIL DOOR AND OPERATING MECHANISM Filed April 5, 1934 2 Sheets-Sheet 2 Zhwentor:

J z. Wzzzza Gttorneg Patented Aug. 11, 1936 JAIL DOOR AND OPERATING MECHANISM John L. Wiliiams, Jackson,- Tenn.

Application April 5, 1934, Serial No. 719,192

3 (Jlaims.

This invention relates to doors and operating mechanism therefor and particularly to the cell doors of prisons, in which the cells are usually arranged in groups or blocks.

In penal institutions it is of the greatest importance to simplify the operation of the doors and to concentrate their control within the reach of a single operator who may operate the doors from a distant point, such as outside the corridor from a control box. One or more doors of a group may be operated individually or the entire group may be operated simultaneously. Any one or more doors may be left in the open position without interfering with the other doors.

One of the objects of my invention is to provide a door which is carried by bearings extending below the floor and above the ceiling of the cell respectively and which may be operated with a minimum of effort.

Another object of the invention is to provide operating mechanism which will automatically hold the door immovable from the inside of the cell either in the open or closed position.

Other objects will be evident from the following description taken in connection with the accompanying drawings in which:

Figure l is a top plan view of the door operating mechanism.

Figure 2 is a vertical sectional view of the con trol box taken on the line 2-2 of Figure 1 showing the crank and sprocket device for operating the door mechanism and the door indicating dial.

Figure 3 is a fragmentary side elevation of the cells showing the semi-circular doors.

Figure 4 is a vertical sectional view taken on the line 4 l of Figure 1.

Figure 5 is a fragmentary transverse sectional view showing the doors in the open and closed positions respectively;

Figure 6 is a detail sectional view of the worm and clutch device of the door-operating mechanism; and

Figure 7 is a schematic illustration of the cams which control the clutches of the door-operating devices.

The doors of the prison cells have heretofore been of the hinged, sliding or vertically rising type and have always required an individual bolt or look. I have provided a semi-circular skeleton door which may be used in an ordinary square cell and which is pivotally mounted to swing on a vertical axis between bearings that are inaccessible from the cell. The operating mechanism embodies a worm and gear actuating device which holds the door rigidly locked in any adjusted position.

The doors H) are skeleton-type, semi-cylindricalfcomprising steel bars l2 rigidly secured to semi-circular upper and lower steel plates i i and reinforced by intermediate semi-circular bars 55. The doors are carried by upper and lower thrust bearings l5 and H. The steel frame bars E8, I?) interlock with vertical flanged door frame bars 28, 2| when the door is inclosed position.

The pivot shaft 23 projecting from the upper door plate, carries a semi-circular gear 24 which meshes with a worm 25, the engaging teeth being cut at an angle such that they jamb and absolutely lock together against any reverse movement applied to the gear carried by the door. Consequently when the door is closed it is automatically locked and cannot be moved by any turning force applied to the door.

The worm 25 is held from longitudinal movement on the shaft 30 by stops 3!, 32, but is free to rotate in the shaft when the clutch teeth on one end are disengaged from the teeth of the sliding clutch member 34 which is splined on shaft 36. v

The clutch 3G is slid on the shaft by the yoke arm of a bell-crank 35 which carries a roller 3%, held in engagement with the periphery of a coacting cam 37 by a retractile spring 38. The cams 37 are rigidly carried by a shaft 48 and are each provided with a peripheral notch in alinement with a notch on each of the other cams and with another notch positioned according to the number or location of the corresponding cell.

The cam-carrying shaft 40 projects into the control box 4| and carries an indicator wheel 43 having a pointer 45 mounted within a circular stationary dial provided with numbers corresponding With the cells. By turning the wheel 43 until the pointer 4'5 is opposite zero on the dial, the shaft 40 will be rotated to a position in which the alined notches on the cams 37 will each be opposite a roller 36, and hence the springs 38 will move all of the clutch members 34 into interlocking engagement with the teeth on the worm members. By turning the crank handle 48 in the control box 4|, thereby rotating the operating shaft 30, the worm and gear mechanism will swing the doors through an angle of from closed to open position. As previously stated, the pitch of the threads of the Worm and the teeth on the gear 24 is such that they lamb and lock against any reverse movement when a turning force is applied to the doors and hence the doors are automatically locked in either closed or open position.

In case the keeper desires to open only one of the doors, for instance the door of cell No. 3, he turns the indicator wheel 43 until the pointer is opposite number 3 on the dial, which will bring the proper notch on the third cam 31 into the position to allow the roller 36 to drop into the notch, as indicated in Fig. '7, and permit the corresponding bell-crank lever 35 to move the clutch into engagement with the teeth on the worm. Then by turning the crank handle 46 until the sprocket 33 on the end of shaft 30 has rotated through the cell door will have swung from closed to open position. This door can remain open while other doors are opened in the same manner in any order desired.

It is obvious that the doors may be closed by moving the indicator wheel to bring the pointer opposite the number of the selected cell and then turning the crank handle in the reverse manner to thereby swing the door from open to closed position. If all of the doors are open,.they may be closed simultaneously by first moving the indicator to bring the pointer opposite zero on the dial which positions the shaft 40 with all of the alined notches over the corresponding rollers 36.

My invention eliminates the use of bolts and locks which have been required heretofore and provides a means of automatically securing or looking the doors upon moving them to closed position. The doors are supported and mounted in such manner that the bearings are not visible from the cells or corridors. The arcuate or semi-circular configuration of the doors permits a simple pivotal mounting upon a vertical axis while the turning effort is reduced to a minimum by employing ball thrust bearings. The worm and gear connection performs a double function, i. e., a door operating device and a locking device. Both the cam positioning shaft and the door operating shaft are longitudinally fixed or immovable.

I have described in detail the particular construction shown in the drawings but it will be evident to engineers that various changes and modifications can be made without departing from this invention and Within the scope of my claims.

I claim:

1. A gang mechanism for controlling the entrance of prison cells, embodying in combination,

a series of semi-cylindrical skeleton steel doors each pivotally mounted to swing about a central axis, operating and locking mechanism therefor comprising a. worm-gear axially secured to the top of each door, a manually rotatable operating shaft having loosely mounted thereon a series of worms in mesh with the respective gears, clutch devices splined on said shaft and normally spring-pressed toward said worms, and a manually operated control shaft having cam mem- 10 bers fixed thereon adapted to control the engagement or disengagement of said clutch devices with said worms, as the control shaft is rotated to predetermined positions, the teeth of said gears and the screw of said worm having 15 a pitch which causes them to lock against reverse movement applied to the door.

2. A self-locking closure for the entrance of a prison cell, comprising a semi-cylindrical skeleton door embodying upper and lower substan- 20 tially semi-circular steel plates connected by a 3. A gang mechanism for controlling the en- 35 trance of prison cells, embodying in combination, a series of semi-cylindrical skeleton steel doors comprising upper and lower substantially semicircular steel plates connected by steel bars, thrust bearings for said doors and which are positioned respectively above and below said upper and lower plates, an operating shaft extending over the cells adjacent said upper bearings, worm gear operatively connecting said shaft with each door to actuate it to open or closed position, said worm gear locking against reverse movement applied to the bars, and a bell-crank lever cooperating with each cam having one arm engaging the periphery of the cam and the other arm operatively connected to the corresponding clutch device, said cams having peripheral 00 notches adapted to receive the bell-crank arm. JOHN L. WILLIAMS. 

